Various techniques and devices for improving the effectiveness of missiles continuously have evolved since missiles were first developed. As a consequence, rocket boosters and airframes place ordnance or instrumentation packages much more precisely than previously envisioned. Typically, a payload is mounted on an airframe which is propelled by a rocket or a rocket booster. The airframe and payload can be ballistically deployed or a controlled guidance can be effected by proper actuation of the motor and suitable control surfaces. Usually, a missile accelerates and velocity increases until the rocket motor thrust ends. The missile continues in an essentially ballistic trajectory until a predetermined command initiates separation of the airframe and payload somewhere along the flight envelope. Separation of the airframe from the payload usually occurs so that the payload is free to accomplish the intended purpose. Separation is accomplished by a variety of well known means, such as, an explosive band cutter that severs a pretensioned band holding the payload and airframe together. Typical of such an arrangement is that shown in the U.S. patent entitled "Rocket-Thrown Missile" of U.S. Pat. No. 3,867,893. Explosive bolt devices and banding are used to hold motors and successive stages together. Helical ejection springs ensure that bivalvular members open away from a payload after the banding has been ruptured. The helical spring was suitable for this design where space limitations were not overly critical. Another clamping arrangement to hold payload and airframe together was shown by Roy M. Kartzmark et al in their U.S. Pat. No. 3,754,725. A tensioning band holds hinged semicircular shells onto a payload and an ejection spring arrangement biases the front end of the shell members apart. The details of the ejection spring arrangement were not shown. From the configuration of this missile it appears that there are no overly critical space constraints between the shells and the missile so that the helical arrangement of the aforecited patent could well be the chosen design.
Thus, there exists in the state-of-the-art a continuing need for a compact biasing arrangement for urging the clamshell-like airframe members from engagement with a missile that is configured to be confined within a small annular space about the payload so as not to interfere with other missile components.